Adaptive query processing in mobile environment

These last years, the evolution of nomadic terminals and mobile networks has yield to the development of the ubiquitous computing. In this context, actual query evaluation and optimization techniques in distributed databases based on the use of a global schema and a cost model are no more relevant. Furthermore, a query processor deployed in this type of environment must face a significant heterogeneity, in particular mobile terminals, communication networks and different data sources. In order to cope with this heterogeneity, such service should have the capability to adapt itself dynamically. In this paper, we describe the problems related to query processing in mobile environment and the needs for adaptability.